My bullmastiff has red bumps on his face?we tried astringent and nothing is working how can we get rid of them, some are bleeding, and it looks sore. Its on his chin and around his mouth

Sounds like he got into something he shouldn't have. Like from another animal, prickly bush, posion ivy. It could be many things. I would wash his entire face, head and neck. Apply neosporin or the like, lightly. Contain him somewhere. At least until you can call a vet. If he is an outside dog, check his area and bedding tomorrow. For now he needs to be cleaned, and contained until you find out what's causing it. I will share this with another user who has much more experience. Good luck.